Automatic ultrasonic cleaning device



July 9,1963 B. RAND 3,096,774

AUTOMATIC ULTRASONIC CLEANING DEVICE Filed March 13, 1961 5 Sheets-Sheet 1 a.....& 5 P v i N 1 1 Al l 7\ INVENTOR.

$8 BURTON RAND n4 BY ATTOR NEY July 9, 1963 a. RAND 3,096,774

AUTOMATIC ULTRASONIC CLEANING DEVICE Filed March 13. 1961 5 Sheets-Sheet 2 9O 84 56 v v 88 Fig. 3

INVENTOR. BURTON RAND 55 BY Cwchflgmm AT TO RN EY July 9, 1963 B. RAND AUTOMATIC ULTRASONIC CLEANING DEVICE 5 Sheets-Sheet 5 Filed March 12 1961 INVENTOR BURTON RAND M A gm ATTORNEY July 9, 1963 B. RAND AUTOMATIC ULTRASONIC CLEANING DEVICE 5 Sheets-Sheet 4 q-I-7 I Filed March 13, 1961 6 n 6 9 8/ I m8 2 B 6 2 4 4 2 4 m '31 m 7 /Z w 4 W 7 4x w 2 2 MW 5 m M 2 IR ATTORNEY July 9, 1963 B. RAND 3,

AUTOMATIC ULTRASONIC CLEANING DEVICE Filed March 15, 1961 5 Sheets-Sheet 5 Fig. 8

242 & 244 200 f :1 '98- ,234 I 250 g use \x 7/ I \V/ I zz 2's INVENTOR.

BURTON RAND BY a 04m ATTORNEY United States Patent 3,096,774 AUTOMATIC ULTRASONIC CLEANING DEVICE Burton Rand, Bala-Cynwyd, Pa., assign'or to The Dow Chemical Company, a corporation of Deiaware Filed Mar. 13, 1961, Ser. No. 95,183 20 Claims. (Cl. 134-79) This invention relates to an automatic ultrasonic cleaning device, and more particularly, to cleaning apparatus for removing grease and hydrocarbon deposits and dirt from machined parts by treatment with solvents such as chlorinated hydrocarbons, trichlorethylene, etc.

The satisfactory and rapid cleaning of small machined parts, such as machined parts which have been buffed, ground or the like presents a most difiicult problem. Experience has shown that notwithstanding repeated submerges in solvents effected by conventional cleaning equipment, an appreciable amount of contaminate in the nature of adhering dirt or the like remains on the machined parts, particularly in the hollows and interstices thereof. The presence of adhering contaminate presents a serious problem where the machined parts are utilized in a structure designed to have close tolerances.

Apparatus utilized heretofore has included an ultrasonic transducer for effecting cleaning of the machined parts by generating cavitation in the solvent. As used heretofore, the machined parts have been transported through the cleaning apparatus in Wire mesh type baskets or the like which are conveyed through the cleaning apparatus by a conveyor system. For example, see US. Patent 2,896,640 which discloses such an apparatus. Of necessity, the cleaning apparatus of the type shown in said patent is relatively large and therefore occupies a substantial amount of floor space in an establishment. As will be made clear hereinafter, the cleaning device of the present invention is capable of performing the same work as the apparatus shown in said patent, but is more efficient and utilizes less floor space.

Cavitation is essentially a gas-filled cavity or bubble which is generated in a liquid by the passage of an intense sound wave through a liquid. The present invention comprehends the generation of cavitation solely in the area of the machined parts and only when the machined parts are juxtaposed to the ultrasonic transducer. In this regard, it will be appreciated by those skilled in the art that most metals are excellent conductors of ultrasonic energy.

The present invention not only provides satisfactory and rapid cleaning of small machined parts such as bolts, intricate forgings, etc. disposed within an open top container, but also is more compact and efficient than in-line production apparatus used heretofore.

It is an object of the present invention to provide a novel cleaning apparatus.

It is another object of the present invention to provide a novel automatic ultrasonic cleaning device which is capable of achieving a high degree of cleaning of small machined parts disposed within a container.

It is another object of the present invention to provide a novel cleaning apparatus wherein machined parts are cleaned in a batch by disposing said parts in a container and subjecting said parts to cavitation generated by an ultrasonic transducer.

It is still another object of the present invention to provide a novel cleaning apparatus wherein the machined parts are mechanically delivered to the cleaning apparatus, mechanically passed through the cleaning apparatus, and mechanically carried away from the cleaning apparatus, completely automatically.

It is a further object of the present invention to provide a novel cleaning apparatus wherein a spoked wheel is "ice provided with a container retention means at the free end of each spoke.

'It is a further object of the present invention to provide a novel cleaning apparatus having an intermittently operated wheel with basket retention means at the free end of each spoke on said wheel, and selectively positionable ultrasonic transducer means reciprocally mounted for movement toward and away from a retention means disposed within a degreasing solvent.

Other objects will appear hereinafter.

For the purpose of illustrating the invention there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

FIGURE 1 is a transverse elevational sectional view partly schematic of the cleaning device of the present invention.

FIGURE 2 is a transverse sectional view taken along the lines 22 of FIGURE 1.

FIGURE 3 is a sectional view taken along the lines 33 of FIGURE 1.

FIGURE 4 is a sectional view similar to FIGURE 2 but of an alternative embodiment.

FIGURE 5 is an enlarged elevational view partly in section of a portion of one spoke of the embodiment shown in FIGURE 4.

FIGURE 6 is a sectional view taken along lines 66 in FIGURE 5.

FIGURE 7 is a sectional view taken along lines 7-7 in FIGURE 5.

FIGURE 8 is a schematic view of the orientating means for the spokes of the embodiment shown in FIGURE 4 for orientating said spokes in their loading and unloading position.

Referring to the drawing in detail, wherein like numerals indicate like elements, there is shown in FIGURE 1 an automatic ultrasonic cleaning device designated generally as 10.

The cleaning device 10 includes a generally rectangular housing 12. A partition wall 14 extends upwardly from the bottom wall of the housing 12 as shown in FIGURE 1. The partition wall 14 divides the bottom portion of the housing 12 into an immersion chamber 16 and a vapor generator sump 18. The chamber 16 is provided with a cleaning solvent such as a chlorinated hydrocarbon, a fiuor inated hydrocarbon such as Freon TF, etc.

The sump 18 is provided with a heating coil 20. The heat from the heating coil 20 vaporizes the solvent within the sump 18 so as to maintain the vapor zone 19. The partition wall 14 maintains the solvent within the sump 18 separate from the degreasing solvent within the immersion chamber 16. Cooling coil-s 22 are provided around the entire inner peripheral wall of the casing 12 as shown in FIGURE 1 to define the upper limit of the vapor zone 19.

A shaft 24 extends horizontally between the walls 26 and 28 of the housing 12. A spoked wheel 30 is rotatably mounted on the shaft 24. The Wheel 30 is provided with an elongated cylindrical, hollow hub 32. The inner periphery of the hub 32 is provided with grooves each receiving an O-ring seal 34. As shown more clearly in FIGURE 1, the O-ring seals 34 are disposed on opposite sides of the spokes of the wheel 30.

The hub 32 surrounds the shaft 24 and has a length greater than the length of the shaft 24. The hub 32 extends through an opening in the wall 28 and is provided with a bearing 38. The lefthand end of the shaft 24, in FIGURE 1, is provided with a bearing 36. The righthand end of the shaft 24 extends beyond the bearing 38.

The righthand end of the hub 32 extends through a bearing suppo1t 40 and is provided with a pulley 42. The

hub 32 and pulley 42 are selectively intermittently rotated by a motor means.

The motor means for intermittently rotating the hub 32 includes a pulley 44 rotatably con-nected to pulley 42 by means of an endless belt 46. The pulley 44 is connected to the output shaft of a six position Geneva movement 48. A Geneva movement is a well known mechanical device for providing intermittent rotary movement. Accordingly, the Geneva movement 48 need not be described in detail. The Geneva movement 48 is connected to the output shaft of a speed reducer 49. The speed reducer 49 is connected to an electrical motor 50.

It will be appreciated by those skilled in the art that other means for providing intermittent rotary motion may be substituted for the Geneva movement 48, speed reducer 49 and motor 50. For example, a time operated clutch or a ratchet and pawl with delay switches may be substituted therefor. The particular type of motor means for providing intermittent rotary motion, per se, forms no part of the present invention.

As shown more clearly in FIGURE 2, the wheel 30 is provided with spokes 51-56 extending radially from the hub 32. While six such spokes have been shown in FIG- URE 2, it will be appreciated that the number of spokes may be increased or decreased as desired in order to effect a predetermined production rate. The free end of each of the spokes 5156 is provided with a container retention means. The container retention means at the free end of each spoke are identical, therefore only one such retention means need be described in detail.

As shown more clearly in FIGURE 1, the retention means at the free end of the spoke 51 includes a cylinder 58 having a reciprocally mounted piston 60 therein. The interengaging faces of the piston 60 and the inner peripheral wall of the cylinder 58 are sealed by means of an O-ring seal. The end of the piston 60 remote from the spoke 51 is provided with a platform 62. The platform 62 lies in a plane which is perpendicular to the longitudinal axis of the spoke 51 and piston 60.

As shown more clearly by 'a comparison of FIGURES 1 and 2, the end of the cylinder 58 remote from the spoke 51 is provided with a hollow rectangular casing 64 which is open at each end. The casing 64 includes side walls 65 which are parallel to the longitudinal axis of the spoke 51 and a lid 66 extending between the side Walls 65 and lying in a plane perpendicular to the longitudinal axis of the spoke 51.

The open ends of the casing 64 are in line with an inlet opening 70 in the wall 28 and an outlet opening 72 in the wall 26. A plurality of spaced rollers 74 are supported within the housing 12 between the inlet opening 70 and the casing 64. A conveyor belt 76 is disposed outside of the housing 12. The conveyor belt 76 is provided with a discharge end adjacent the inlet opening 70. The con veyor belt 76 is adapted to deliver container 78 to the cleaning device of the present invention. The containers 78 may be boxes, baskets of the wire mesh type, etc. The cleaning device 10 of the present invention is primarily designed to accommodate containers 78 which lack a top wall or lid. Containers of this type may be referred to hereinafter as containers of the open top type. However, as will be made clear hereinafter, the cleaning device 10 of the present invention will accommodate containers which include a lid.

As shown more clearly in FIGURE 1, the conveyor belt 76 is disposed in an inclined plane. Accordingly, the belt 76 is provided with spaced cleats 80. The cleats 80 may be dispensed with if the conveyor belt 76 is horizontally disposed. The containers 78 are provided with bumpers 82 for a purpose to be made clear hereinafter.

Means are provided for selectively reciprocating each piston radially outwardly so that a container is maintained secure between each platform and lid in all positions of the spokes except for the position of spoke 51 in FIG- URES 1 and 2 which is the loading and unloading posi-' tion. As shown more clearly in FIGURES 2 and 3, this last mentioned means includes a fluid inlet conduit 84 and a fluid outlet conduit 86 disposed within the lefthand end of the shaft 24. The conduit 84 is provided with a passage 88 at the one oclock position as shown more clearly in FIGURE 3. Preferably, the passage 88 is provided with an enlarged end adjacent the periphery of the shaft 24.

The fluid outlet conduit 86 is in communication with a passage 90 located at the eleven oclock position as shown more clearly in FIGURE 3. Prefer-ably, the passage 90 is of reduced diameter so as to provide a slow bleed to atmosphere. Also, the passage 90 is preferably provided with an enlarged portion adjacent the periphery of the shaft 24. Thus, the cylinder 58 is in communication with atmosphere by way of the hollow spoke 51, passage 90, and outlet conduit 86 in the position of spoke 51 as shown in FIGURES 1-3.

The lefthand end of conduit 86 communicates with atmosphere by way of outlet pipe 92. The lefthand end of fluid inlet conduit 84 is in communication with an inlet pipe 94. The inlet pipe 94 is provided with a pump 96 which delivers pressurized air to the inlet conduit 84.

A piston housing 98 is mounted within the housing 12. The piston within the housing 98 is provided with a piston rod 100. An ultrasonic transducer 102 is connected to the piston rod 100'. A supply and exhaust conduit 104 extends from the housing 98 through wall 26 of the housing 12. to a supply and exhaust valve 106-.

The supply and exhaust valve 106 is provided with an inlet pipe 108 and an outlet pipe 118. The inlet pipe 108 is provided with a pump 112 for delivering pressurized fluid to the housing 98. The supply and exhaust valve 106 is preferably provided with a solenoid operator 114. The solenoid coil of the solenoid operator 114 is connected to a time delay relay 116 which is in series with a switch 118. The relay 116 and switch 118 are connected across a source of electrical potential. 'lI'he switch 118 is provided with a push button operator It is to be emphasized that the relative position of the elements 98 and 184-116 is merely for purposes of illustration. In actual practice, these elements are above the vapor zone 19 and bars connect the piston rod 100 to a platform which supports the transducer 102. The illustration of these elements above the vapor zone 19 unnecessarily complicates the drawing.

As shown more clearly in the upper lefthand corner of FIGURE 1, a plurality of spaced rollers 120 are mounted within the housing 12 between the casing 64 and the outlet opening 72. A switch 122 having an actuator 1 24 is mounted on the wall 26 below the rollers 120. The switch 122 is in series with a solenoid 126. The solenoid 126 has a finger 128. The switch 122 and the solenoid 126 are connected across a source of electrial potential.

An endless conveyor 130 is disposed along the lefthand side of the housing 12 in FIGURE 1. The endless conveyor .130 is disposed in an inclined plane with the upper end of the conveyor 130 disposed adjacent the outlet opening 72. The endless conveyor 130 includes a flexible belt disposed around 'a driving roller 132 and a driven roller 133. The driving roller 132 is operatively connected with a motor 134 by means of an endless belt or chain 136.

A time delay switch is mounted adjacent inlet opening 70. An incoming container 78 actuates the switch 140* which permit-s current to actuate solenoid 142. The solenoid .142 actuates the supply and exhaust valve 144 which permits pressurized fluid to move a piston, not shown, within housing 146. This last mentioned piston is provided with a piston rod 148 having a pivot joint 150 which permits a slight amount of pivotation.

The free end of the piston rod 148 is provided with a pivotably mounted jaw 15 2. A cam 154 is provided on the piston rod 148 so that the free end of the piston rod 148 pivots counter clockwise about joint 150 as the cam 154 passes over rod 156 which is fixed within the housing 12.

The automatic ultrasonic cleaning device of the present invention operates in the following manner:

The conveyor belt 76 delivers a container 78 to the device 10 of the present invention in timed sequence corresponding to the intermittent rotative movement of the wheel 30. The momentum of the container 78 causes the same to move across the roller 74 into the casing 64. In the position of spoke 51, the cylinder 58 is in communication with atmosphere by way of the hollow spoke 51, the passage 90, conduit 86, and outlet pipe 92. Accordingly, piston 60 is in its lowermost position.

The intermittently operated motor means causes the spoke 51 to rotate sixty degrees to the position formerly occupied by spoke 52. In this position, the cylinder 58 is in communication with a source of pressurized air by way of the hollow spoke 5 1, passage 88, inlet conduit 84, and inlet pipe 94. The pressurized fluid causes the piston 60 to reciprocate in a radial direction until the upper peripheral surface of the container 78 is abuttingly contacting the lid 66.

After a set predetermined period, the wheel 30 is indexed another sixty degress so that spoke 51 occupies the position of spoke 53 shown in FIGURE 2. After another predetermined period, the wheel 30 is indexed another sixty degrees so that spoke 51 occupies the position of spoke 54 shown in FIGURE 2. As the casing 64 moves into the last mentioned position, it contacts the operator 119 for the switch 118 thereby enabling current to pass through the time delay relay 116 to the solenoid operator 114. The solenoid operator 114 actuates the supply and exhaust valve 106 so that a pressurized fluid is conveyed by means of inlet pipe 108 and fluid conduit 104 beneath the piston position within the housing 98. The piston causes the piston rod 100 to move the transducer 102 from the phantom position shown in FIGURE 1 to the solid line position shown in FIGURE 1. The solid line position of the transducer 102 places the transducer in abutting contact with the lid 66.

The alternating current for operating the transducer 102 is supplied thereto by means of wires (not shown). The transducer 102 is operative simultaneous with the operation of motor 50. The ultrasonic energy is readily conducted by the metallic lid 66 so as to generate cavitation solely within the container '78. It should be noted that the container 7 8 in this position is upside down. Since the upper peripheral surface of the container 78 is in abutting contact with the inner peripheral surface of the lid 66, the container 7-8 need not have a cover or lid.

The time delay relay 116 is set to interrupt the flow of current to the solenoid operator 114 before the motor means indexes the wheel 30 another sixty degrees. When the time delay relay 116 interrupts the flow of current, the solenoid operator 114 causes the supply and exhaust valve 106 to place the chamber beneath the piston within housing 98 in communication with atmosphere by way of conduit 104 and outlet pipe 110. Immediately thereafter, the predetermined period during which the spoke 51 occupies the position of spoke 54 in FIGURE 2 expires and the motor means indexes the wheel 30 another sixty degrees so that spoke 51 now occupies the position of spoke 55- in FIGURE 2.

After a predetermined period, the motor means rotates the wheel 30* another sixty degrees so that spoke 51 now occupies the position of spoke 56- in FIGURE 2. After another predetermined period, the motor means indexes the Wheel 30 another sixty degrees so that spoke 51 occupies the position shown in FIGURE 2. As said spoke 51 moves to the position shown in FIGURE 2, the pressurized fluid which had been trapped beneath the piston 60 now escapes to the outlet pipe 92 by way of the passage and conduit 86. It will be noted that the passage 90 has a diameter less than the diameter of conduit 86. This enables the piston 60 to reciprocate radially inwardly without an abrupt descent. Due to the location of passage 90, the fluid trapped beneath piston 60 begins to exhaust at a point corresponding to the eleven oclock position shown in FIGURE 3.

This piston rod 148 is provided for withdrawing the container of clean machined parts from the casing 64 so that the container rolls on the rollers toward the conveyor belt 130. As a new container 78 trips switch 140, the solenoid 142 is actuated for a short period of time during which time pressurized air urges a piston within housing 146 against a spring. Movement of the piston causes piston rod 148 to move to the right in FIG- URE 1. The movement of the piston rod 148 moves the pivotable jaw 152 over the forward wall of the container of cleaned parts.

Thereafter, the time delay switch shuts off the current to the solenoid 142. Then, the spring within housing 146 returns the piston to its normal position as the valve 144 is in its exhaust position. As the piston rod 148 moves to the left in FIGURE 1, the jaw 152 withdraws the container of cleaned parts from within the casing 64. As the cam 154- rides over the rod 156, the free end of rod 148 pivots about joint 150, thereby permitting the container to freely move on the rollers 120 As the container of cleaned machine parts pass over the rollers 120, the bottom of the container trips the switch actuator 124 thereby directing current to the sole noid 126. The switch 122 is provided with a timed delay mechanism so that the solenoid 126 in its energized condition raises the finger 128 to the phantom position shown in FIGURE 1 for a predetermined period of time. During this last mentioned predetermined period of time, a new container of machined parts is delivered to the casing 64. The finger 128 prevents the new container from passing all the way through the casing 64.

It will be appreciated that each of the spokes 51-56 are provided with a container of machined parts in the above manner so that a container is being loaded and unloaded in the position of spoke 51 while another container is being subjected to ultrasonic energy in the position of spoke 54. In the positions of spokes 53 and 55, the machined parts are within the vapor zone 19. In the position of spoke 54 in FIGURE 2, the container is dis posed within the solvent in the immersion chamber 16 and is selectively subjected to cavitation generated by the ultrasonic transducer 102. The transducer 102 should be connected to the piston rod 100 in any acceptable manner well known to those skilled in the art so as to prevent the loss of ultrasonic energy into the piston rod 100 and casing 98.

The upper surface of the platforms 62 are preferably corrugated. In this manner the boxes or containers will only have line contact with the platforms 62. Thus, friction between the platforms 62 and the containers is substantially reduced thereby facilitating the entry and removal of the containers with respect to the casings 64.

In certain instances, it is desirable to index the spokes through arcs of thirty degrees instead of sixty degrees. In this manner, the parts are immersed within the solvent in chamber 16 before and after being subjected to the cavitation generated by transducer 102. The intermittent operation of the transducer renders the machine 10 more efficient than those known heretofore.

Since the present invention uses a spoked wheel, the apparatus uses less floor space than comparable cleaning devices.

FIGURES 4-8 disclose an alternative embodiment of the present invention designated generally as 10. The machine 10 is identical with the machine 10 except for the structural features which will be discussed hereinafter.

As shown more clearly in FIGURE 4, which is a sec- 7 tional view similar to FIGURE 2, the machine 10' is provided with a wheel 30 having a hub 32 and an odd number of spokes. As shown, the wheel 30' is provided with seven spokes 151-157. The reason for providing wheel 30' with an odd number of spokes will be made clear hereinafter.

The structure of the spokes 151-157 differs from the structure of the spokes 51-56. A means is provided for rotating the spokes 151-157 about their longitudinal axis in all positions of the spokes except for the loading and unloading position. Such means may assume a variety of equivalent forms which will readily suggest themselves to those skilled in the art. As shown, such means comprises a chain drive means 160 The chain drive means 160 includes a chain 162 meshingly engaged with a gear on each of the spokes 152157. Since the spoke 151 in FIGURE 4 is in the loading and unloading position, the chain 162 is not meshingly engaged with the gear on the spoke 151.

The chain 162 is rotatably driven by a gear 164 rotatably mounted on a shaft 166. The shaft 166 is supported on a platform 168. The chain 162 is required to pass between the teeth on the gear 164 and an upright portion 170 on the platform 168. In this manner, the chain 162 will by-pass the gear on the spoke 151 when said spoke 151 is in the loading and unloading position.

The shaft 166 is rotatably driven by a beveled gear 172 fixedly secured thereto. The beveled gear 172 is meshingly engaged with a beveled gear 174. The beveled gear 174 is rotatably driven by a motor 176 supported on the platform 168. Suitable guides 178 and 180 are provided on opposite sides of the platform 168 to guide the chain 162.

The spokes 151-157 are identical. Accordingly, it is deemed necessary to only describe one spoke in detail. As shown more clearly in FIGURE 5, spoke 151 includes a spoke portion 182 rotatable about its longitudinal axis with respect to the spoke portion 184. One end of the spoke portion 184 is connected to the hub 32. The other end of the spoke portion 184 is disposed within a bushing 186 and separated from one end of the spoke portion 182 by a ball bearing 188. The gear 190 is fixedly secured to the outer periphery of the bushing 186. In all positions other than the loading and unloading position, the teeth on the gear 190 will be meshingly engaged with the chain 162. p The end of the spoke portion 182 remote from the ball bearing 188 is fixedly secured to a cylindrical housing 192. One end of a load shaft 194 is disposed within the housing 192. A cylindrical load pin 196 extends perpendicularly from the shaft 194 through a slot 198 in the housing 192. The slot 198 is elongated in a direction corresponding to the longitudinal axis of the spoke 151 and is provided at its radially outermost point with an offset portion 200.

A casing cylinder 202 is disposed around the shaft 194. The pin 196 also extends through a slot 204 in the lowermost end of the casing cylinder 202 which is disposed within the housing 192 and is provided with a flange 206. A spring 208 is disposed between the flange 206 and a flange 210 on the lowermost end of the shaft 194.

The outer peripheral surface of the casing cylinder 20-2 is fixedly secured to the inner periphery of a flange 212. The flange 212 is removably secured with respect to the housing 192. Accordingly, the casing cylinder 202 is incapable of moving in a radial direction with respect to the housing 192.

The end of the shaft 194 remote from the flange 210 is provided with a platform 214 corresponding to platform 62 in the machine 10. The end of the casing cylinder 202 remote from the flange 206 is provided with a casing 216 comparable to the casing 64 of the machine 10. The casing 216 has resilient compressible cushions 217 to accommodate the movement of the pin 196 into the offset portion 200.

A platfrom218 is provided within the machine 10' on the opposite side of the wheel 30' from the chain drive means 160. The platform 218 supports an air cylinder housing 220. A piston 222 is biased to a lowermost position within the housing 220 by a spring 224. A conduit 226, which is adapted to be connected to a source of air pressure, extends upwardly through an aperture in the platform 18 and. an aperture in the lowermost wall of the air cylinder housing 220. A piston rod 228 is connected at one end to the piston 222. The other end of the piston rod 228 extends through an aperture in the top wall of the air cylinder housing 220 and is provided with a head 230 having a beveled uppermost surface. The head 230 is disposed directly below the pin 196.

A solenoid 232 is mounted above the platform 218. The armature 234 on the solenoid 232 is disposed at a level corresponding with the position of the offset portion 280 of the slot 198 in the housing 192. The inactive position of the solenoid armature 234 is shown in full lines in FIGURE 5. The phantom position of the solenoid armature 234 is shown in dotted lines in FIGURE 5.

As shown more clearly in FIGURE 4, the wheel 30' is provided with seven spokes. A transducer 236 is mounted on the bottom wall of the housing for the machine 10' at an angle with respect to the bottom wall within the solvent 238. The transducer 236 is disposed adjacent to the peripheral path of the wheel 30, but spaced therefrom by a distance corresponding to a whole number of wavelengths of ultrasonic energy within the solvent 238. While spoke 151 is having a basket unloaded and a new basket of parts to be cleaned is being loaded into a basket retention means on the end of the spoke 151, the baskets retained at the ends of the spokes 153-156 are being rotated in a direction about the longitudinal axis of the respective spokes. While the basket retention means and basket at the end of spoke 154 is being rotated, the parts to be cleaned and located within this basket are being subjected to cavitation in the solvent 238 generated by the transducer 236. At the same time, the machined parts within the basket at the end of spoke 154 are being tumbled due to the angular relationship of the spoke 15.4 and the rotary movement thereof. If an even number of spokes were provided on the wheel 30', the above mentioned relationship would not exist. That is, 'a tumbling action in conjunction with a cavitation cleaning action could not be attained simultaneously.

It is intended that the basket of machined parts be subjected to cavitation for a period of approximately thirty seconds. Accordingly, it is necessary for the chain drive means 160 to rotate the spokes at a relatively slow rate of speed. For example, it is intended that the chain drive means 160 rotate the spokes 151-157 between two and four revolutions per minute. While a basket at the end of spoke 154 is being subjected to cavitation, the baskets at the ends of spokes 153 and 156 are rotating within the vapor zone 240 and the basket at the end of spoke is rotating within the solvent 238.

The chain 162 must be capable of being bent in two perpendicular directions. A chain of this nature is commercially available, therefore need not be described in detail. I have found it necessary to provide other guides for the chain 162 similar to the guides 178 and 180.

It is believed that the operation of the machine 10' will be obvious from the description above relating to the operation of the machine 10. One aspect of the operation of the machine 10 which is not present in the operation of the machine 10 is the problem involved in obtaining alignment between the inlet and outlet apertures of the machine 10' and the casing 216. As the spoke 151 passes out of the influence of the chain drive means 160, the casing 216 continues to rotate. The rotation of the casing 216 must be stopped in a position so that the casing 216 is properly disposed for unloading of the basket and the receiving of a new basket of machined parts. To assure that the casing 216 is properly aligned,

orientating means are provided. Such orientating means include parallel fiat surfaces 242 and 244 on each of the spokes 151-157.

The flat surfaces 242 and 244 have a length greater than the distance between the flat surfaces. Plate-like guides 246 and 248 are disposed within the machine at the unloading and load-ing position of the spokes. The guides 246 and 24-8 taper inwardly slightly from their entrance end. The guide 248 is substantially longer than the guide 245 and is more flexible than the guide 246 so that the tapered portion on guide 248 will flex slightly when contacted by a spoke. If a spoke is not properly orientated with respect to the inlet and outlet of the machine 10, the flat surfaces 242 and 244 will cont-act the leading edge of the guides 246 and 248 thereby causing the spoke to rotate about its longitudinal axis so as to be received between the guides 246 and 248.

It will be understood that the machine 10 is provided with all of the corresponding structure shown in machine 10 so as to provide a completely operative device. In addition, machine 10' is provided with timing switches for sequentially operating the solenoid 232 and a supply and exhaust valve for supplying air to the conduit 226.

Thus, it will be seen that the embodiment designated generally as 10' includes a rotatably mounted wheel intermittently operated by a motor means and a chain drive means for continuously rotating less than all of the spokes about their longitudinal axis so that machined parts will be subject to a tumbling action and a cavitation action simultaneously.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification as indicating the scope of the invention.

I claim:

1. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a wheel within said housing having spokes extending from a hub, said hub being rotatably mounted on a shaft within said housing, a cylinder at the end of each spoke, a reciprocally mounted piston within each cylinder, each spoke being hollow, means including the hollow spokes for selectively reciprocating said pistons in a direction radially outwardly from said hub, each cylinder having a container retention means thereon, each piston being adapted to secure a container against a portion of said container retention means, an ultrasonic transducer disposed within the solvent adjacent the periphery of said wheel, and means for intermittently rotating said wheel so that each of said container retention means is disposed within the solvent adjacent said transducer for a predetermined period of time.

2. In an apparatus in accordance with claim 1 including means for intermittently reciprocating said transducer with respect to said container retention means.

3. In an apparatus in accordance with claim 1 wherein said means for intermittently rotating said Wheel is connected to said hub, and O-ring seals between said hub and said shaft on opposite sides of the plane of said spokes.

4. In an apparatus in accordance with claim 1 wherein said means for reciprocating said pistons includes a conduit for directing a pressurized fluid into a hollow spoke at one rotative position thereof, said pressurized fluid being trapped within said one spoke and its associated cylinder until said one spoke reaches another predetermined rotative position wherein said trapped fluid is permitted to escape thereby enabling the piston on said one spoke to move radially inwardly toward said hub.

5. In an apparatus in accordance with claim 1 wherein said housing includes a vapor generator sump having a heating coil, a vapor zone above said sump and solvent, each container retention means passing through said vapor zone before and after being immersed within said solvent.

6. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a sump having a heating coil therein, a partition wall separating said immersion chamber and sump, a vapor zone above said immersion chamber and sump, a rotatably mounted spoked wheel in said housing, container retention means on the ends of the spokes for receiving a container of machined parts, means for preventing machined parts from falling out of a container in all rotative positions of said wheel, at least one ultrasonic transducer within said solvent adjacent the periphery of said wheel, mechanicfl means connected to said wheel for intermittently rotating said wheel so that each of said container retention means and a container adapted to be mounted thereon is immersed in said solvent for a predetermined period of time adjacent said transducer, means for selectively moving said transducer radially inwardly to a first position for a predetermined period of time and for moving said transducer radially outwardly to a second position after the expiration of said last mentioned predetermined period of time.

7. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a rotatably mounted spoked wheel in said housing, container retention means on each of the spokes of said wheel for receiving a container of machined parts, at least one ultrasonic transducer within said solvent adjacent the periphery of said wheel, means connected with said wheel for intermittently rotating said wheel so that each of said container retention means are immersed in the solvent for a predetermined period of time adjacent said transducer, said wheel having a loading and an unloading position, an inlet in said housing for loading each container retention means at said loading position, and an outlet in said housing for unloading each retention means at said unloading position, and a mechanical means for separating containers from each of said retention means in the unloading position, said mechanical means being responsive to the loading of a container which passes through said inlet into said housing.

8. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a rotatably mounted spoked wheel in said housing, container retention means on each of the spokes of said wheel for receiving a container of machined parts, at least one ultrasonic transducer within said solvent adjacent the periphery of travel of said container retention means, motor means connected with said wheel for intermittently rotating said wheel so that each of said container retention means are immersed in said solvent for predetermined period of time adjacent said transducer, said wheel having a common loading and unloading position for the spokes of said wheel, an inlet to said housing for loading each container retention means at said loading position, an outlet in said housing for unloading each container retention means at said unloading position, and means within said housing for rotating the container retention means on less than all of said spokes about the longitudinal axis of said spokes.

9. In a cleaning apparatus in accordance with claim 8 wherein said last mentioned means includes a continuously operated chain drive means.

10. In a cleaning apparatus in accordance with claim 8 including an orientation means supported within said housing for properly orientating each container retention means in alignment with the inlet and outlet to said housing as each container retention means approaches the loading and unloading position.

11. In a cleaning apparatus in accordance with claim 8 wherein said spoked wheel is provided with an odd number of spokes, said ultrasonic transducer being disposed at an angle with relation to the bottom wall of said housing,

11 whereby parts to be cleaned will be subjected to tumbling and cavitation simultaneously.

12. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a vapor zone above said solvent, said vapor zone being defined by cooling coils within said housing, a rotatably mounted spoke-d wheel in said housing, container retention means mounted at the end of each spoke on said wheel, each container retention means including a platform movable in a direction coincident with the longitudinal axis of its respective spoke, at least one ultrasonic tranducer within said solvent adjacent the periphery of said wheel, motor means connected with said wheel for intermittently rotating said wheel so that each "of said container retention means are immersed in said solvent for a predetermined period of time adjacent said transducer, and each spoke being disposed with- 'in said vapor zone prior to being rotated to a position wherein its respective container retention means is juxtaposed to said transducer.

13. In a cleaning apparatus for degreasing machined parts comprising a housing having an immersion chamber adapted to contain a degreasing solvent, a vapor zone above said solvent, said vapor zone being defined by cooling coils within said housing, a rotatably. mounted spoked Wheel in said housing, container retention means mounted at the end of each spoke on said wheel, each container retention means including a'platform movable in a dire=c tion coincident with the longitudinal axis of its respective spoke, at leastone ultrasonic transducer within said solvent adjacent the periphery of said wheel, motor means connected with said wheel for intermittently rotating said wheel so that each of said container retention means is immersed in said solventfor a predetermined period of time adjacent said transducer, each spoke being disposed with in said vapor zone prior to being rotated to a position wherein its respective container retention means is juxtaposed to said transducer, means provided for simultaneously rotating each container retention means when it is juxtaposed to. said. transducensaid wheel having an odd-number of spokes, and said transducer being disposed at'an angle with relation to a bottom wall on said housing. 7

14. In a cleaning apparatus for degreasing machined parts comprising. a' housing havingan immersion charm her, said chamber beingadapted tocontain a degreasing solvent, a rotatably mounted hubin said housing, said hub having a plurality of radially extending spokes, container retention means on each of said spokes. forreceiving a container of machined parts, means connected to said hub for intermittently rotating said hub and spokes so that each of said container retention means are immersed in the solvent for a predetermined period of time, each retention means including a support platform mounted for reciprocation along the longitudinal axis of its respective spoke, said spokes having a loading and an unloading position, at least one ultrasonic transducer within the solvent adjacent the periphery o f the rotary path of the said container retention means said'housing having an inlet for loading each container retention means at said loading position, and said housing having an outlet for unloading each retention means at said unloading position. ,7

15. In an apparatus in accordance with claim 14 wherein said spokes are hollow, said last mentioned means including fluid conduits in communication with said cylinders for selectively placing said cylinders in communication with a supply of pressurized air and atmosphere.

16. In an apparatus in accordance with claim 14 including an ultnasonic transducer within said housing, means for selectively positioning said transducer adjacent one of said container retention means for a predetermined period of time and for withdrawing said transducer away from said last mentioned container retention means while said last mentioned container retention means is immobile within said solvent.

17. In a'n'apparatus in accordance with claim 14 Wherein 'each'retention means includes a lid, the lid of each retention means being radially outwardly from the platform of each, retention means, and means for selectively reciprocating each platform radially outwardly so that a container is maintained secured between each platform and its respective lid in all positions of said spokes except for the loading and unloading positions, whereby the parts each container are able to tumble as said spokes are [rotated between the loading and unloading positions.

18. A cleaning apparatus in accordance with claim 7 wherein means are provided forrotating a container retention means about an axis of rotation corresponding to thelongitudinal'axis of its respective spoke when the last mentioned container retention means is juxtaposed to the ultrasonic transducer.

19. In a cleaning apparatus in accordance with claim 7 wherein said ultrasonic transducer is disposed at an angle with relation to the bottom wall of said housing, said wheel being provided with an odd number of spokes, whereby parts to be cleaned will be subjected to tumbling and cavitations simultaneously.

20. In a cleaning apparatus in accordance with claim 7 wherein each'container retention means includes a lid and a reciprocably. disposed platform, and means for selectively reciprocatingieach platform radially outwardly toward its respective lid so that a container may be secured therebetween in all positions of the spokes except for the loading and unloading positions.

References Cited in the file of this patent UNITED STATES PATENTS 1,640,643 Brusson Aug. 30, 1927 2,673,835 Kearney Mar. 3 0, 1954 2,808,064 Kearney Oct. 1, 1957 2,972,997 McCown Feb. 28, 1961 3,022,202 McCown Feb. 20, 1962 FOREIGN PATENTS 449,174 Great Britain June 22, 1936 

1. IN A CLEANING APPARATUS FOR DEGREASING MACHINED PARTS COMPRISING A HOUSING HAVING AN IMMERSION CHAMBER ADAPTED TO CONTAIN A DEGREASING SOLVENT, A WHEEL WITHIN SAID HOUSING SPOKES EXTENDING FROM A HUB, SAID HUB BEING ROTATABLY MOUNTED ON A SHAFT WITHIN SAID HOUSING, A CYLINDER AT THE END OF EACH SPOKE BEING MOUNTED PISTON WITHIN EACH CYLINDER, EACH SPOKE BEING HOLLOW, MEANS INCLUDING THE HOLLOW SPOKES FOR SELECTIVELY RECIPROCATING SAID PISTONS IN A DIRECTION RADIALLY OUTWARDLY FROM SAID HUB, EACH CYLINDER HAVING A CONTAINER RETENTION MEANS THEREON, EACH PISTON OF SAID CONTAINER RETENTION A CONTAINER AGAINST A PORTION OF SAID CONTAINER RETENTION MEANS, AN ULTRASONIC TRANSDUCER DISPOSED WITHIN THE SOLVENT ADJACENT THE PERIPHERY OF SAID WHEEL, AND MEANS FOR INTERMITTENTLY ROTATING SAID WHEEL SO THAT EACH OF SAID CONTAINER RETENTION MEANS IS DISPOSED WITHIN THE SOLVENT ADJACENT SAID TRANSDUCER FOR A PREDETERMINED PERIOD OF TIME. 